condition mean min max ZT0-3 3.7071433333333332 3.148225 4.70031 ZT4-7 4.559670000000001 4.559670000000001 4.559670000000001 ZT8-11 10.26725 10.26725 10.26725 ZT12-15 7.4536999999999995 6.0429949999999995 8.864405 ZT16-19 5.975885 5.975885 5.975885 ZT20-23 5.131565 5.131565 5.131565